What is DNA?
DNA stands for deoxyribonucleic acid. DNA is the molecule that carries the genetic information used by a cell for the creation of proteins. DNA contains the genetic instructions used in the development and functioning of all known living organisms. The main role of DNA molecules is the long term storage of genetic information. DNA is often compared to a set of blueprints for humans.
The genetic code was a mystery until biologists discovered the structure of DNA as a spiral ladder. The information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C), and thymine (T). Each step of the ladder is a pair of bases, and an A only binds to a T and C only binds to a G. DNA is a chemical sequence of these bases in two strands that are bound to form a double helix. The order of these bases along a DNA strand is known as the DNA sequence.
DNA stands for deoxyribonucleic acid. In 1869 Friedrich Miescher discovered DNA which he called “nuclein,” because it was in the nucleus of the cell. Miescher was unable to fully appreciate the significance of his finding. Scientific inquiry has since revealed that DNA contains the biological instructions for the form and function of all known living organisms. DNA is often referred to as a blueprint for life.
DNA remained a mystery until scientists discovered that DNA had the structure of an intricate spiral staircase, or double helix. The stair rails are made-up of alternating sugars and phosphates, and each stair step is composed of two nitrogen bases and a hydrogen bond. There are four nitrogen bases in DNA: adenine (A), thymine (T), guanine (G), and cytosine (C). In the pairing of the bases, A only bonds with T and C only pairs with G; the two bases together form what are called base pairs.
An article in the journal Nature by James D. Watson and Francis Crick in 1953 first unveiled the secrets of DNA’s double helix. Maurice Wilkins and Rosalind Franklin are also credited with this discovery.
Human Genome Project
A genome is all of an organism’s genetic information encoded in its DNA. The United States Department of Energy and the National Institutes of Health, along with several international partners, completed the mapping of the human genome in 2003. They identified the genes in human DNA and determined the sequence of the 3 billion chemical base pairs that are in human DNA. The Human Genome Project was completed in thirteen years, two years ahead of schedule. If you want to continue learning about DNA click here!